"It retains the capabilities it had in its original form, except it exchanges its original race for the new one and changes its racial traits accordingly."

Going from human to, say halfelf: do I lose the extra language, as that is a racial trait?

It seems odd if I do. I mean, it's strange to suddenly lose the ability to speak a certain language...

No, you're not able to speak Hafling because you're a Hafling. You LEARNED how to speak Hafling cause you're one.  Therefore you still know the language, however you don't learn the racial language of the new race.

And heres another, new, d100 list for the spell: https://www.dndbeyond.com/posts/410-critical-role-spotlight-episode-49

5e's Reincarnate is far more generous than previous versions.  Time was, 50/50 shot you came back as an animal. 

I like this spell. Unlike other resurrection spells, this one can actually make you young again. With enough gold and always having a friendly druid around, one could live forever.

Why are liches a thing? Seriously. It is like living forever but with no overt side effects. Or a clone? 

Didn't this use to cause you to lose all your old memories?

Keeps languages and proficiencies.

What about racial trait bonuses, like the extra pluses to attributes?

If the "Sending" spell is cast at someone who has reincarnated...would it connect?  the soul is the same person but the body is totally different.  would the person casting the spell be thinking of the person they knew or the soul of the person they knew? 

one of my players is searching for his lost sister.  she was killed by orcs then reincarnated by a local druid tribe that knew her mother.  my player is a cleric and might cast sending...what do I do?

Quote from DagonDraconis >>

No, you're not able to speak Hafling because you're a Hafling. You LEARNED how to speak Hafling cause you're one.  Therefore you still know the language, however you don't learn the racial language of the new race.

Btw, Dragonborns can speak draconic since hatching, as it is partially passed down from their mothers, genetically. What then? 

The intention of the spell is that anything that came from the original race is lost and replaced by the new race.
This includes things like fey ancestry, aasimar healing hands, half orc relentless endurance.
And things like lizardfolk hunters lore skills and half elf extra skills.
Raw (and I believe based off the wording, as intended) you also replace your starting language
As that comes packaged with the race

So you lose everything from the original race (I'd assume you'd get a refund if you took a racial feat for the original race though. If a DM doesn't let you do that they are a ****** in my book)

Quote from GenericRpgNPC01 >>

So you lose everything from the original race (I'd assume you'd get a refund if you took a racial feat for the original race though. If a DM doesn't let you do that they are a ****** in my book)

I'd just let you keep the racial feat. That's a fun kinda call back to what you used to be. I guess if it triggers off the feature, that's a bummer. 

Quote from Jarrenitis >>

If the "Sending" spell is cast at someone who has reincarnated...would it connect?  the soul is the same person but the body is totally different.  would the person casting the spell be thinking of the person they knew or the soul of the person they knew? 

one of my players is searching for his lost sister.  she was killed by orcs then reincarnated by a local druid tribe that knew her mother.  my player is a cleric and might cast sending...what do I do?

 Taking a metaphysical standpoint in answering this... 

The Weave can be manipulated in various ways, but the way sorcerers gain access to their abilities has to do with their bloodline, not their soul. One could therefore postulate that the weave exists as a field that is only able to engage with material concepts. The soul goes beyond the material, and so I would say that the weave simply does not bend in the same way. 

Arguably, a DM with a vengeance could use this argument to reincarnate a high level sorcerer into a low level wizard. 

Does anyone know where to find an updated race table that includes all of the current races? Everything I find only goes up to Volo's Guide to Monsters.

Quote from MHopman1990 >>

The Weave can be manipulated in various ways, but the way sorcerers gain access to their abilities has to do with their bloodline, not their soul. One could therefore postulate that the weave exists as a field that is only able to engage with material concepts. The soul goes beyond the material, and so I would say that the weave simply does not bend in the same way. 

 This is only true for Draconic Bloodline sorcerers. There are many other types of sorcerous origins, one of which is Divine Soul:

"Sometimes the spark of magic that fuels a sorcerer comes from a divine source that glimmers within the soul."

Quote from MHopman1990 >>

Arguably, a DM with a vengeance could use this argument to reincarnate a high level sorcerer into a low level wizard. 

 I think you could make an argument similar to this for Draconic Bloodline sorcerers, but they wouldn't have any reason to become a low-level wizard.

Wizards study magic as if they are peering into the code of reality and messing with it to achieve their desired effects. It takes tremendous knowledge and research and mental effort.

Sorcerers ARE an embodiment of magic in some way, and therefore can naturally manipulate reality as an extension of their will. The skills just aren't transferable.

Regardless, I would discourage this route without discussing it with the player to see if they find it narratively interesting. And I would suggest picking a non-spellcasting class that reflects their other skills. Or perhaps even a Wild Soul sorcerer or even Divine Soul with some narrative tie to how they retained their connection to magic. You could even make some interesting cases for Warlock with the right patron.

What voldemort should've done.

Yeah but then you have to be a Gnome sometimes

I believe not, since language is just memorizing word meanings, and you keep your memory.